With the development of virtual reality (VR) technologies, the VR technologies are applied in increasingly more industries to display business-relevant images more vividly and realistically.
For example, in a VR house viewing system in the industry of real estate agency, when a user enters a virtual three-dimensional house model, for an object in a space, the user only can get information on shape and rough volume in the space, but cannot precisely perceive a specific dimension of the object. For users, however, the specific dimensional information on the object is particularly important. For example, for a sofa a user sees in a three-dimensional space, the user might want to know the sofa's length and width, so as to determine how it will look if the sofa in his/her own home is placed here, and how much space the sofa will take. Or when seeing a certain room, the user might want to know the room's length and width, so as to determine dimensions of furniture such as bed, cabinet and sofa suitable to this room.
Therefore, how to reasonably demonstrate a spatial size marking so as to more intuitively and more clearly indicate a spatial size of a real room and thereby improve immersive experience of users becomes a problem that needs to be addressed.